Water Pump

When draining the coolant, keep in mind that cats and dogs are attracted by the ethylene glycol antifreeze, and are quite likely to drink any that is left in an uncovered container or in puddles on the ground. This will prove fatal in sufficient quantity. Always drain the coolant into a sealable container. Coolant should be reused unless it is contaminated or several years old.

Disconnect the hoses at the pump.

Remove the fan belt.

Unbolt the fan and hub assembly.

Unbolt and remove the pump.

Installation is the reverse of removal. Torque the pump bolts to 17 ft. lbs. Always use a new gasket coated with sealer.

Fig. Fig. 1: Cooling system components on the 6-232 and 6-258 engines

Fig. Fig. 2: Cooling system components on the 8-304 engine

4-150 Engine

Some 4-150 engines with air conditioning are equipped with a serpentine drive belt and have a reverse rotating water pump coupled with a viscous fan drive assembly. The components are identified by the words REVERSE stamped on the cover of the viscous drive and on the inner side of the fan. The word REV is also cast into the body of the water pump.

Drain the cooling system.

CAUTION

When draining the coolant, keep in mind that cats and dogs are attracted by the ethylene glycol antifreeze, and are quite likely to drink any that is left in an uncovered container or in puddles on the ground. This will prove fatal in sufficient quantity. Always drain the coolant into a sealable container. Coolant should be reused unless it is contaminated or several years old.

Disconnect the hoses at the pump.

Remove the drive belts.

Remove the power steering pump bracket.

Remove the fan and shroud.

Unbolt and remove the pump.

To install:

Clean the mating surfaces thoroughly.

Using a new gasket, install the pump and torque the bolts to 13 ft. lbs.

Install the fan and shroud.

Install the power steering pump bracket.

Install and adjust the drive belts.

Connect the hoses at the pump.

Fill the cooling system.

4-151 Engine

Remove the fan belt.

Remove the fan and hub assembly.

Drain the cooling system.

CAUTION

When draining the coolant, keep in mind that cats and dogs are attracted by the ethylene glycol antifreeze, and are quite likely to drink any that is left in an uncovered container or in puddles on the ground. This will prove fatal in sufficient quantity. Always drain the coolant into a sealable container. Coolant should be reused unless it is contaminated or several years old.

Disconnect the hoses at the pump.

Unbolt and remove the pump.

Installation is the reverse of removal. Always use a new gasket coated with sealer. Torque the water pump bolts to 25 ft. lbs. Tighten the fan and hub bolts to 18 ft. lbs.

6-225 Engine

Drain the cooling system.

CAUTION

When draining the coolant, keep in mind that cats and dogs are attracted by the ethylene glycol antifreeze, and are quite likely to drink any that is left in an uncovered container or in puddles on the ground. This will prove fatal in sufficient quantity. Always drain the coolant into a sealable container. Coolant should be reused unless it is contaminated or several years old.

Disconnect all hoses at the pump.

Remove the drive belts.

Remove the fan and hub assembly.

Unbolt and remove the water pump along with the alternator adjustment bracket.

Installation is the reverse of removal. Always use a new gasket coated with sealer. Torque the water pump bolts to 6-8 ft. lbs.

6-232 and 6-258 Engines

Drain the cooling system.

CAUTION

When draining the coolant, keep in mind that cats and dogs are attracted by the ethylene glycol antifreeze, and are quite likely to drink any that is left in an uncovered container or in puddles on the ground. This will prove fatal in sufficient quantity. Always drain the coolant into a sealable container. Coolant should be reused unless it is contaminated or several years old.

Disconnect all hoses at the pump.

Remove the drive belts.

Remove the fan shroud attaching screws.

Unbolt the fan and fan drive assembly and remove along with the shroud. On some models it may be easier to turn the shroud
1
/
2
turn.

Unbolt and remove the pump.

Engines built for sale in California having a single, serpentine drive belt and viscous fan drive, have a reverse rotating pump and drive. These components are identified by the word REVERSE stamped on the drive cover and inner side of the fan, and REV cast into the water pump body. Never interchange standard rotating parts with these.

Installation is the reverse of removal. Always use a new gasket coated with sealer. Torque the water pump bolts to 13 ft. lbs.; the fan bolts to 18 ft. lbs.

8-304 Engine

Drain the cooling system.

Disconnect all hoses at the pump.

Loosen all drive belts.

Remove the shroud, but reinsert one bolt to hold the radiator.

Remove the fan and hub.

If the vehicle is equipped with A/C install a double nut on the compressor bracket-to-water pump stud and remove the stud.

Remove, but do not disconnect the alternator and bracket.

If so equipped, remove the nuts that attach the power steering pump to the rear half of the pump bracket.

Remove the two bolts that attach the front half to the rear half of the bracket.

Remove the remaining upper screw from the inner air pump support bracket, loosen the lower bolt and drop the bracket away from the power steering front bracket.

Remove the front half of the power steering bracket from the water pump mounting stud.

Unbolt and remove the water pump.

To install:

Install the pump. Always use a new gasket coated with sealer. Torque the pump-to-timing case bolts to 48 inch lbs. and the pump-to-block bolts to 25 ft. lbs.

Install the front half of the power steering bracket to the water pump mounting stud. Torque the power steering pulley nut to 60 ft. lbs.

Install the upper screw from the inner air pump support bracket, and tighten the lower bolt.

If so equipped, install the nuts that attach the power steering pump to the rear half of the pump bracket.

Install the two bolts that attach the front half to the rear half of the bracket.

Install the alternator and bracket.

If the vehicle is equipped with A/C install a double nut on the compressor bracket-to-water pump stud and install the stud.

Install the fan and hub.

Install the shroud.

Adjust all drive belts.

Connect all hoses at the pump.

Fill the cooling system.

Fig. Fig. 3: Remove the fan retaining bolts

Fig. Fig. 4: Remove the fan from the pulley

Fig. Fig. 5: With the fan removed, you can remove the pulley

Fig. Fig. 6: Remove the bypass hose retaining clamp from the water pump

Fig. Fig. 7: Disconnect the bypass hose from the water pump

Fig. Fig. 8: Remove the upper mounting bolt at the alternator bracket

Fig. Fig. 9: Disconnect the heater hose from the water pump

Fig. Fig. 10: Remove the lower water pump mounting bolts

Fig. Fig. 11: Remove the upper water pump mounting bolts

Fig. Fig. 12: With all of the bolts removed, pull the water pump off of the timing cover

Fig. Fig. 13: Remove the old gasket. Be sure to clean the mating surface before installing a new gasket